Rotary turbine



Nov. 22, 1966 H. BACHL 3,286,984

ROTARY TURBINE Filed Dec. 27. 1965 s SheetsSheet 1 Nov. 22, 1966 H. BACHL ROTARY TURBINE 5 Shee ts-Sheet 2 Filed Dec. 27, 1965 H. BACHL ROTARY TURBINE Nov. 22, 1966 5 Sheets-Sheet 5 7 Filed Dec. 27, 1965 United States Patent ROTARY TURBINE Herbert Bach], Turkenstrasse 40/11, Munich, Germany Filed Dec. 27, 1965, Ser. No. 516,481 11 Claims. (Cl. 25379) This application is a continuation in part of my copending application Serial No. 227,477, filed October 1, 1962, now Patent No. 3,226,085 dated December 28, 1965 assigned to the assignee of the present application.

This invention relates to a flow turbine with at least one rotor and one guidewheel which together form one stage. The number of stages may be increased as desired by means of an appropriately large number of rotorand guide-wheels. I

The term guidewheel generally implies that, contrary to a rotor, this wheel relates to a stationary component. However in a flow turbine machine only the effect of the relative movement between the rotor and guidewheels is essential to the operation, so that there is no necessity to make the guidewheel stationary, but only that there be relative movement between the guidewheel and the 1otor. However, it may also be possible that the guidewheel revolves or rotates at a slower or, perhaps, at a higher speed than the rotor, so that a relative speed becomes eifective between the rotor and guidewheel. Since flow turbines operate most economically at high speed of rotation this implies that the relative speed should be as high as possible. Therefore, virtually no practical value can be gained from letting the guidewheel rotate with a lower or a higher speed than the rotor. Only the reversal of the rotation direction becomes eifective, whereby in special cases the guidewheel is formed by a second guidewheel which rotates in the opposite direction and at the same speed as the rotor.

The present invention issues from the above general concept of this type of flow turbine, in which at least one of the two components, i.e. the rotor or the guidewheel on the one hand, or the rotor or contra-rotating rotor on the other hand, are respectively designed as a massive or solid body inside of which the flow path is worked-in or formed in the form of channels. In the description which follows, this solid body always relates to the rotor. Its opposite part, which in the following description is always referred to as a guidewheel or guide element, may also be developed in an analogous manner as a solid body with channels positioned inside it, but may also have the conventional blades or guide fins, shovels, etc.

Rotary machines with tangential flow directions at the outer periphery of the rotor have become known from the above-mentioned copendin-g application Serial No. 227,- 477, filed October 1, 1962. Machines of this type aflord the opportunity of applying flow turbines or machines to high pressure magnitudes (x greater than 1.0), small delivery magnitudes, large diameter magnitudes and small rated speeds per stage, thereby extending the use of said machines to an area previously reserved for piston machines. However, a tangential embodiment of the channel inlets having radial inflow direction at the outer rotor periphery results in a discharge through thin edges which are highly stressed by the centrifugal forces, so that high peripheral speeds cannot be utilized in the interest of stability. A connection of guiding components on the outside, in a radial direction, by means of nozzles, ducts, or ditfusors) requires much space and material.

In order to overcome these disadvantages, and in accordance with one feature of the invention, the channels which guide the working medium in the rotor are made so as to discharge in an axial direction, so that an ade- 3,286,984 Patented Nov. 22, 1966 quate overlap or cover remains at the rotor periphery. The succeeding flow path occurs with the use of rotors.

For example, if a centrifugal flow-direction is chosen, the working medium near the center of rotation, as viewed in a meridian section, enters axially into the rotor and is deflected within the latter in a known manner into a radial flow direction. In a view perpendicular to the center of rotation, the working medium is not carried by blades, but rather by channels which are curved in front and in back in the form of blades, but which differ from the latter by having a relatively large concentration of mate-rial in the center region of the rotor. These channels change into a tangential or almost tangential direction near the outer diameter of the rotor. Seen in the meridian section, an axial flow direction again follows after the tangential one, so that the working medium in the rotor flows axially in the area of the lowest as well as the highest peripheral speed. Thereby, the axial flow may be limited to an axial component of an essentially radial, tangential or spirally running flow. The boundary or outer limiting edge of the tangential section may be divided into one or more axial blades, or changed into the same. The sequence of flow is reversed from the foregoing in a centripetal flow direction.

The above-mentioned application Serial No. 227,477, of which the present application is a continuation-in-part application, discloses the structure of the rotor as being a massive body with inside channels formed therein and a guide for its flow channels in such a manner that the latter start near the shaft and having predominantly axial direction components; and in the region of increased volume, gradually, in a continuous curve are deflected-into an essentially radial direction and finally upon reaching the outer region of the rotor at a continuous curve flow through the inlet opening cross section in a substantially tangential manner, or at an angle which deviates only slightly from a tangent.

The present invention constitutes a further development and improvement of this principle. The tangential flow outlet at the outer cylinder housing area may only be realized approximately, from the technical sense, since the channel walls must be divided into razor-edged blades, but such blades could not withstand the high centrifugal forces present therein. Hence, these edges need to be rounded off and a true tangential outlet may only be approximately eflected.

By contrast, the present invention aims at effecting a deflection of the flow, in the region of the channel inlets, in such a way that the flowing medium emerges at the front face of the rotor. Now the channel walls may be so formed, Without danger, so as to assure an exact tangential outlet (outflow).

The technical advantages of this construction over the known radial machines lies in the cfact that at small throughput values, a much higher supply rate per stage is obtained when using high rotating values and smaller outside diameters. Furthermore, space and material may be saved for the guide elements, used to guide the flow in a radial direction. At low relative speeds, which are slightly accelerated or decreased in the rot r, a high rate of efiiciency may likewise be expected.

The foregoing and more specific objects and features of my invention will be described in the following .with reference to embodiments of rotary turbines according to the invention illustrated by way of example on the accompanying drawings in which:

FIG. 1 is a perspective exploded view showing various parts of the turbine machine according to the invention;

FIG. 2 is a side View of the device of FIG. 1 in assembled condition;

FIG. 3 is a fragmentary axial section through the rotor, stator and shafts of a turbine according to the invention;

FIG. 4 is a view taken "along the plane of line 1V-1V of FIG. 3;

FIG. is a schematic flow diagram of the device of FIGS. 3 and 4 taken along a spacially curved surface to better illustrate the relative flow through the respective channels;

FIG. 6 is a fragmentary sectional view at the outer periphery of a modification of the device of FIGS. 3 and 4, showing a collector channel;

FIG. 7 is a fragmentary sectional view showing a further modification of the device of FIGS. 3 and 4;

FIG. -8 is an exploded perspective view of a rotor, collector channel and guidewheel of a further modification wherein the [guidewheel is fi-t within and is surrounded by the collector channel;

FIG. 9 is a perspective view, in cross section, of a further modification of a collector channel in the member is provided with curved blades;

FIG. is a side view, in half-section, of a multistaged flow turbine machine according to a further modification of the invention, wherein the collector channels are part of a common ring body, and both collector channels contain spacially curved blades.

FIGS. 11 and 12 illustrate schematically in fragmentary cross section further features of the invention and directions of flow through the channels;

FIG. 13 illustrates another embodiment of the invention in axial section through the flow channels;

FIG. 14 is a View taken along line XIVXIV of FIG. and

FIG. 15 is a side view of the flow channels of the turbine of FIGS. 13-14.

The figures illustrate the main parts of the various embodiments necessary :for the understanding of the invention.

The basic principle of the invention is illustrated in FIGS. 3, 4 and 5, where one and the same embodiment is shown in various views. Shaift 1 is hollow and is provided with an inner shaft 1a and a rotor 2, the latter rotating with and mounted on the shaft v1. The guide wheel 3, mounted on shaft 1a, is either stationary or else rotates in the opposite direction to rotor 2. The rotor 2 contains a number of flow channels 4, 5 and 6 formed therein which start in axial direction at the outer front face 7 of the rotor 2. The flowing medium enters in the direction of arrows 8 and 9 of FIG. 3, into these channels and is deflected inside them into a radial flow direction, whereby the channels 4, 5, 6 then lead in a generally centrifugal direction to the outer region of the rotor.

FIG. 4 illustrates the inner face of this channel guide and the flow channels 4, 5 and 6. In reality, these flow channels describe specially curved spiral paths of an essentially fiat type with one or more loops, which therefore extend to an angle of at least 360". Since, in addition, the channels are also spacially curved, the channel guidewheel cannot be realistically illustrated by the usual type of section illustrations. Therefore, the section areas in FIG. 5 does not constitute a plane, .but rep-resents a curved and even spacially curved section areas. In this manner, as FIG. 5 shows by contrast to FIG. 3 one arrives at completely different illustrations for the same design.

FIG. 5 illustrates the blade-shaped design of the wall 10 between the two openings 11 and 12 of the adjacent channels. Here, the working medium flows in the direction of the arrows 13 and 14 into the channels 15 and 16 of the guidewheel 3. In FIG. 3, these channels are indicated by the numerals 15 and 16. Here, the guidewheel 3, similar to the rotor 2 is constructed as a massive solid body with worked-in channels. The working medium leaves said channels near the shaft 1, in the direction of arrows 17 and 18.

A further, optional feature of the invention, consists in forming the junction between the rotor 2 and the guidewheel 3 by interposing a collector channel. FIG. 6 shows a ring-shaped collector channel 19 interposed between the rotor 2 and the guide wheel 3. Among other things, this collector channel serves for the purpose of reducing noise. If necessary, the collector channel may also contain appropriate blade or channel elements for guiding the flow, for example, guide blades 20 or the like. be stationary in its entirety, or it may be rotatable. The

collector channel may rotate by itself, or it may rotate.

together with the rotor 2 or with a guidewheel 3. The guidewheel 3 is a contra-rotating rotor relative to rotor 2. Furthermore, as FIG. 7 shows, the collector channel 19a may bring about a deflection into a radial flow direction, so that now the flow which reaches the collector channel in the direction of arrow 21 is so deflected that it enters into the channel 15 of the guidewheel 3 in the axial direction of arrow 22. The colleetor channel 19a in this embodiment now overlaps into the guidewheel 3. In FIG. 8 there is shown in a perspective illustration an exploded 'view of a rotor, collector channel and a guidewheel, the rotor and guidewheel being enclosed by the collector chamber.

The deflection of the flow within the collector channel 19 may occur with the aid of spacially curved blades 23, as shown in the perspective illustration according to FIG. 9.

FIG. 10 shows a multi-staged turbine flow machine which operates according to the above principles, whereby the collector channels 19 and 24 belong to a common or mutual ring body 25. The collector channel 19 as well as 24 contains spacially curved blades, indicated with the numeral 26, located in the collector channel 24. As previously mentioned, the entire ring body 25 may either be stationary or rotatable, and particularly may be connected with a rotor such as 2 or a guidewheel rotor 3 rotating in the opposite direction. Within the collector channels 19, the flow may be led over a larger angle, for example Several embodiments or modifications may be employed for the guide elements. For example, they may be positioned in disc shape between the rotor and guidewheel stages, i.e., at centrifugal flow in the rotor, also axially or tangentially entering or flowing in at the outer periphery and with subsequent radial return-channels toward the center or axis of rotation; the return channels may be designed also as nozzles or diifusors. For reducing noise the rotor blades can direct the flow into a collecting channel, either axially or tangentially, as described in copending above-mentioned application Serial No. 227,477, with the guide blades following the collector channel in an axial or tangential manner.

Also, according to the present invention, the collector channel may be designed as part of the rotor, insofar as at least one component of the absolute speed at the rotor outlet has the same direction as the peripheral speed. This latter design would be for the purpose of reducing frictional losses, so that the collector channel would reach over or overlap the radially or tangentially, starting or emerging guide blades (see FIG. 4). Or the blades branching off from the tangential section of the rotor channels could be axially led at first and then end up in a radial direction, so that junction between rotor and guide body again as in Ger-man Patent 962,762, on

a cylindrical surface which is concentric to the center of rotation, but in this case occurs between stationary guide elements and rotory elements overreaching the former, and with or without interposing a collector ring space. In this latter embodiment, the channel inlets may run radially or tangentially.

The collector channel 19 may In FIG. 5 a number of rotor stages are combined into a closed rotational body which rotates about the stationary inner shaft which carries the guide elements and, hence, in the last described embodiment the junctions in the meridian section do not lie in the axial but rather in the radially flowing part of the entire flow path.

As shown in the schematic drawing of FIG. 5, the axial component of the flow in the outer region of the rotor may be limited to a spacial curve of the tangential channel section. The flow medium may be led between the rotor-and guide body also near the axis through a collector channel and the channel may be discharged either radially or-with extreme pre-twist-tangentially or almost tangentially, so that the deflection in the radial channels of a rotor stage reaches an angle of almost 180.

It will be obvious to those skilled in the art, upon studying this disclosure, that devices according to my invention can be modified in various respects and hence may be embodied in apparatus other than that particularly illustrated and described herein, without departing from the essential features of my invention and within the scope of the claims annexed hereto.

I claim:

1. A rotary turbomachine for low rated speed values having a plurality of stages provided with rotors and guidewheels wherein the working medium flows through the first rotor stage successively in a continuous spiral downstream direction first axially, then radially and then in a predominantly axial direction relative to the rotational axis of the machine, and wherein the working medium, as viewed in a section perpendicular to said rotational axis, flows through channels which are curved forwardly toward the outer periphery of a respective rotor and then rearwardly toward said rotational axis, the fluid leaving said channels at the outer periphery of the rotors in a substantially tangential direction, whereby the initially axial flow currents may be selectively limited to axial components of a predominantly radial, tangential or spiral-shaped flow current.

2. Machine according to claim 1, said machine having means for directing the working medium to flow through said channels in a generally centrifugal direction.

3. Machine according to claim 1, said machine having means for directing the working medium to flow through said channels in a generally centripetal direction.

4. Machine according to claim 1, at least one of said rotors being provided near its periphery with blade means which change the flow direction of the working medium from a radial into an axial flow direction.

5. Machine according to claim 1, said guidewheels being arranged between said rotors and being rotatable in a direction opposite to the rotational direction of a respective adjacent rotor.

6. Machine according to claim 2, said guidewheels having flow channels for guiding the working medium in a generally radial direction, said guide channels defining nozzle means to direct the flow back toward the rotational axls.

7. Machine according to claim 3, said guidewheels having flow channels for guiding the working medium in a generally radial direction, said guide channels defining difiusor means to direct the flow away from said rotational axis.

8. Machine according to claim 5, said guidewheels being located so as to ctorm a flow-junction with respective adjacent rotor, said junction, as viewed in meridian section, being within the radial flow portion of the entire flow path of the working medium, so that the rotor and adjacent guidewheel overlap, whereby the channel outlets may be directed perpendicular to rotational axis either radially or tangentially.

9. Machine according to claim 8, including a collector ring forming a flow channel and being located around at least one of said flow-junctions between a respective rotor and guidewheel, said. collector ring being adapted to receive axial and radial flows from a respective rotor or guidewheel.

10. Machine according to claim 9, said collector ring defining guide faces having flow channels of a substantially spiral shape, whereby the channel outlets of the rotor and guidewheels, as viewed in section, flow outwardly in a direction perpendicular to said rotational axis and discharge into said collector channel substantially tangentially.

11. Machine according to claim 9, said collector ring defining guide faces having flow channels of a substantially spiral shape, whereby the outlets of the rotor and guidewheels, as viewed in section, flow outwardly in a direction perpendicular to said rotational axis and discharge into said collector channel substantially radially.

References Cited by the Examiner UNITED STATES PATENTS 1,990,059 2/1935 Bertin 253-79 1,993,963 3/1935 Heinze 253-79 X 2,945,670 7/1960 Caddell 253-88 X FOREIGN PATENTS 142,662 7/ 1903 Germany.

MARTIN P. SCHWADRON, Primary Examiner.

E. A. POWELL, JR., Assistant Examiner. 

1. A ROTARY TURBOMACHINE FOR LOW RATED SPEED VALUES HAVING A PLURALITY OF STAGES PROVIDED WITH ROTORS AND GUIDEWHEELS WHEREIN THE WORKING MEDIUM FLOWS THROUGH THE FIRST ROTOR STAGE SUCCESSIVELY IN A CONTINUOUS SPIRAL DOWNSTREAM DIRECTION FIRST AXIALLY, THEN RADIALLY AND THEN IN A PREDOMINANTLY AXIAL DIRECTION RELATIVE TO THE ROTATIONAL AXIS OF THE MACHINE, AND WHEREIN THE WORKING MEDIUM, AS VIEWED IN A SECTION PERPENDICULAR TO SAID ROTATIONAL AXIS, FLOWS THROUGH CHANNELS WHICH ARE CURVED FORWARDLY TOWARD THE OUTER PERIPHERY OF A RESPECTIVE ROTOR AND THEN REARWARDLY TOWARD SAID ROTATIONAL AXIS, THE FLUID LEAVING SAID CHANNELS AT THE OUTER PERIPHERY OF THE ROTORS IN A SUBSTANTIALLY TANGENTIAL DIRECTION, WHEREBY THE INITIALLY AXIAL FLOW CURRENTS MAY BE SELECTIVELY LIMITED TO AXIAL COMPONENTS OF A PREDOMINANTLY RADIAL, TANGENTIAL OF SPIRAL-SHAPED FLOW CURRENT. 